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The Fermi paradox revisited: Technosignatures and the contact era

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Re: The Fermi paradox revisited: Technosignatures and the contact era

#331

Post by dredmorbius »

credit_guy wrote: post #325
dredmorbius wrote: post #299

Earlier quoted context omitted.

Rocket propulsion benefits from directional discharge. Project Orion lead to the investigation prospects for nuclear shaped charges , in which the blast is highly directional. The concept was developed further in the colourfully-named "Casaba-Howitzer": https://en.wikipedia.org/wiki/Casaba-Howitzer > Odds are reasonably good that any space-faring civilisation would create similarly directional reaction devices for sp…

Cool link about the Casaba howitzer. Thank you.

A relatively recent discovery of mine, and ... interesting to contemplate.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#332

Post by friend_and_foe »

lapcat wrote: post #246
friend_and_foe wrote: post #235

Earlier quoted context omitted.

Really? You don't see how our civilization is stronger than it's ever been? You don't see how we are on the verge of expanding beyond our home planet? Just, don't see it huh? Perhaps you're not the person that should be explaining to everyone what is painfully obvious and what is not then.

> Perhaps you're not the person that should be explaining to everyone what is painfully obvious and what is not then. You didn't even understand my comment. I meant it's painfully obvious to me. It should have been obvious that I didn't mean it was obvious to everyone, but obviously some people can't see the obvious. I could write a long essay on why we're not on the verge of expanding beyond our home planet, but I f…

If I could change your mind would we still be doomed?

Re: The Fermi paradox revisited: Technosignatures and the contact era

#333

Post by DesiLurker »

actionfromafar wrote: post #323
DesiLurker wrote: post #277

Earlier quoted context omitted.

its inverse square falloff for radio energy dissipation so I'd say it goes away really really quickly. also you have the problem of overcoming Sun's 'blaring' background signal unless you took your signal generator and placed it outside of oort cloud or further.

Another idea is to put a mylar parabolic mirror behind the bombs. A very short burst of light is going to get focused in a beam before the mylar is vapourised. Maybe someone smart here could calculate exactly how short the beam would be. That short burst could be in itself a significant signature. What, in nature, could produce such a short concentrated energy burst?

problem with such a tight-beam is you have to be in direct line of sight for it to be seen. which means a very small number of receivers civilization can ever know, that is exact opposite of the goals of a 'lighthouse'. perhaps something that sweeps around at regular intervals with some precession thrown in for coverage, that makes it closer to GP's comment about neutron star emitting prime numbers.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#334

Post by anotherman554 »

withinboredom wrote: post #270
anotherman554 wrote: post #216

Earlier quoted context omitted.

If you look at animals on earth, they just aren't curious about many of the things we are curious about. My cats for example don't find television interesting. Suppose there's some property of physics that looks like random noise to us (maybe like a TV looks like random noise to a cat) but to a different species they see it's something they can model and understand while our species just ignores it?

Your cats don’t find the tv interesting because they can’t even see it. Their visual refresh rate is different enough from humans that they just see flashes of images (a refresh rate above 100hz is needed for cats to watch tv or see a screen, IIRC).

I don't think making Youtube videos go at 4x speed will result in more interest from the cats, but I'll test it later.

Of course the TV thing was just an example, cats don't pass the mirror test (If you put red dye on one part of their face they show no interest in how their face looks different when looking in a mirror).

Re: The Fermi paradox revisited: Technosignatures and the contact era

#335

Post by withinboredom »

anotherman554 wrote: post #334
withinboredom wrote: post #270

Earlier quoted context omitted.

Your cats don’t find the tv interesting because they can’t even see it. Their visual refresh rate is different enough from humans that they just see flashes of images (a refresh rate above 100hz is needed for cats to watch tv or see a screen, IIRC).

I don't think making Youtube videos go at 4x speed will result in more interest from the cats, but I'll test it later. Of course the TV thing was just an example, cats don't pass the mirror test (If you put red dye on one part of their face they show no interest in how their face looks different when looking in a mirror).

The speed of the YouTube video doesn’t matter, it’s the refresh rate of the tv or monitor that matter. With a tube tv or older lcd screen, it just looks like a flashing gizmo.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#336

Post by drowsspa »

seanw444 wrote: post #51
drowsspa wrote: post #42

Earlier quoted context omitted.

That sounds like a non-issue. Our conscience already "pauses" when we go to sleep or get hit in the head, we already have people being resuscitated...

What if consciousness is something that can only be revived, with the revival of the body, a short period of time after the body "shuts down"? Like its own non-physical life form, for lack of better description. We focus on the preservation of the body when talking about this stuff. But maybe the pattern of "waking up from normal sleep" doesn't hold true over such a time span? Of course there's no scientific rebuttal…

I don't find it interesting at all. Other than wishful thinking I don't see any reason to suppose that consciousness is special or non-physical. I think it will become like the assumptions that the Earth was the center of the Universe or humans were different from other animals.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#337

Post by friend_and_foe »

lapcat wrote: post #322
dromenkoning wrote: post #320

Earlier quoted context omitted.

> I could write a long essay on why we're not on the verge of expanding beyond our home planet The reason that essay would be long is because you'd have to explain away so much progress from multiple independently operating space industries.

"progress" We have a handful of humans living temporarily in Earth orbit. We have precisely zero humans living permanently off planet. That's not much progress toward a self-sustaining space colony millions of miles away in an extremely hostile environment. We don't even know whether the human body can survive long term in the much lower gravity of Mars. Life on Earth didn't evolve for that. The whole idea could be d…

I'd call going from nobody ever having been to space to a handful people living in space seasonally for work progress. Define progress?

Re: The Fermi paradox revisited: Technosignatures and the contact era

#338

Post by anotherman554 »

withinboredom wrote: post #335
anotherman554 wrote: post #334

Earlier quoted context omitted.

I don't think making Youtube videos go at 4x speed will result in more interest from the cats, but I'll test it later. Of course the TV thing was just an example, cats don't pass the mirror test (If you put red dye on one part of their face they show no interest in how their face looks different when looking in a mirror).

The speed of the YouTube video doesn’t matter, it’s the refresh rate of the tv or monitor that matter. With a tube tv or older lcd screen, it just looks like a flashing gizmo.

I have a 120 hz Oled Android TV. Unless Youtube drops frames speeding up a 30 FPS video 4x should hit 120 FPS.

I've never heard of someone filming a video for cats in 4x slow motion and asking people to play it at 4x to entertain a cat, so I'm assuming this experiment has been tried and doesn't work, but I'll give it a shot.

(It occurs to me I would need to confirm the Android Youtube app supports 120 FPS otherwise I'd need to play something through a PC).

Re: The Fermi paradox revisited: Technosignatures and the contact era

#339

Post by withinboredom »

anotherman554 wrote: post #338
withinboredom wrote: post #335

Earlier quoted context omitted.

The speed of the YouTube video doesn’t matter, it’s the refresh rate of the tv or monitor that matter. With a tube tv or older lcd screen, it just looks like a flashing gizmo.

I have a 120 hz Oled Android TV. Unless Youtube drops frames speeding up a 30 FPS video 4x should hit 120 FPS. I've never heard of someone filming a video for cats in 4x slow motion and asking people to play it at 4x to entertain a cat, so I'm assuming this experiment has been tried and doesn't work, but I'll give it a shot. (It occurs to me I would need to confirm the Android Youtube app supports 120 FPS otherwise I…

I’m not talking about FPS. At all. It doesn’t matter how many FPS there are. I’m talking about the refresh rate, ie, how many times per a second the hardware updates the screen which is in no way related to FPS, which is how many times per second your video card fills the display buffer.

Re: The Fermi paradox revisited: Technosignatures and the contact era

#340

Post by aaroninsf »

superposeur wrote: post #102

In my opinion, the excitement occasioned by the discovery of so many exoplanets has clouded our collective judgement on the Fermi Paradox, leading the overwhelmingly most probable resolution to be underemphasized. Namely: there is no life out there. Not due to baroque mechanisms such as techno-self-destruction but just due to its sheer unlikeliness. As large as the number of stars in the observable universe is (let’s…

There is a pitfall with this line of argument in that it is appeal to intuition in a domain in which we have none, because we have no ability to intuit about large numbers.

That doesn't mean that it's wrong (though I myself think that it is); but appeals to "sheer unlikeliness" should be made with care because they can rely on facts such as "the chance for a given star system hosting a planet on which even simple life emerges is 1 in 10^X" hence "oh my 1 in 10^X is a very small number!". Where what matters is e.g. how that number compares to the number of such star systems. Etc etc.

Predictive value aside, the Drake equation at least attempts to quantify.

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